There has been increasing emphasis on the application of robotics technology to various industrial uses. The Robot Institute of America defines a robot as a "Reprogrammable, multi-functional manipulator designed to move materials, parts, tools, or specialized devices through various programmed motions for the performance of a variety of tasks". The field of robotics is a rapidly developing area of technology.
In general, there are two main types of robots. The digital or non-servo type of robot is typically actuated by fluid cylinders and is characterized by on/off operation. The other type is servo robots, also known as analog or proportional robots, which can be actuated by fluid cylinders or electrical actuators and are characterized by usage of a feedback signal for control purposes. In addition, there are various classes of both types of these robots, depending upon their degree of intelligence. Those types of robots which combine characteristics of the servo and non-servo types are generally known as hybrid robots.
The pick-and-place robot is a type of non-servo robot which utilizes double-acting cylinders, usually pneumatic, each having only extended or retracted positions such that their operation is characterized by an on/off or digital function. Most such robots are based on a fairly simple set of X, Y, and Z axes set perpendicualr to each other so that their arms tend to operate on cylindrical or Cartesian coordinate systems. As a result, such robots tend to be of limited use and must be custom-adapted to particular operations. Further, such robots cannot be readily adapted to perform other operations and are thus difficult to reprogram without extensive mechanical adjustments. Heretofore such robots have not utilized articulated arms.
A need has thus arisen for an improved pick-and-place robot incorporating an articulated arm which is adapted to facilitate reprogrammability by changing the operating envelope.